RUS  ENG
Full version
JOURNALS // Fizika Tverdogo Tela // Archive

Fizika Tverdogo Tela, 2020 Volume 62, Issue 12, Pages 2034–2046 (Mi ftt8218)

This article is cited in 5 papers

Metals

Study of properties of gold–iron alloy in the macro- and nanocrystalline states under different $P$$T$ conditions

M. N. Magomedov

Institute of Geothermy Problems, Joint Institute for High Temperatures, Russian Academy of Sciences, 367030, Makhachkala, Russia

Abstract: Parameters of the Mie–Lennard-Jones pair interatomic potential for a disordered substitutional fcc-Au–Fe alloy are determined. The concentration dependences of the lattice properties of a macrocrystal of this alloy are calculated based on these parameters. The results of calculating twenty properties of fcc-Au, fcc-Fe, and fcc-Au$_{0.5}$Fe$_{0.5}$ macrocrystals showed good consistency with the experimental data. The equation of state $P(\nu,T;N)$ and baric dependences of both the lattice and surface properties of the fcc-Au$_{0.5}$Fe$_{0.5}$ alloy are calculated using the RP nanocrystal model. The calculations have been performed at temperatures $T$ = 100, 300, and 500 K for both the macrocrystal $(N=\infty)$ and the cubic nanocrystal consisting of $N$ = 306 atoms. It is shown that, during isothermal–isobaric $(P=0)$ decrease in the nanocrystal size, its Debye temperature, elastic modulus, and specific surface energy decrease, while its specific volume, coefficient of thermal expansion, specific heat, and Poisson ratio increase. At low temperatures, the specific surface energy increases in a certain range of pressures with an isothermal–isobaric decrease in the number of atoms in the nanocrystal. This range of pressures disappears with an increase in temperature.

Keywords: gold, iron, substitutional alloy, nanocrystal, equation of state, elastic modulus, thermal expansion, surface energy.

Received: 21.08.2020
Revised: 21.08.2020
Accepted: 27.08.2020

DOI: 10.21883/FTT.2020.12.50206.172


 English version:
Physics of the Solid State, 2020, 62:12, 2280–2292

Bibliographic databases:


© Steklov Math. Inst. of RAS, 2025